Centrifugal governor



Oct. 25, 1932. A. REHM ET-AL 1,884,233

'CBNTRIFUGAL GOVERNOR Fixed Feb. ze. 1931 Patented Oct. 25,1932

UNITED STATES 'PATENT oFFrcE .ALFRED Bm, F STUTTGART, THEODOB WOLFF, 0F ESSLINGEN, AND WILHELI WALTHEB, 0F STUTTGART, GEBIANY, ASSIGNOB'S TO ROBERT BOSCH AKTIENGE- 0F STUTTGART, GERMANY Application lcd February 28, 1981, Serial No. 518,514, and in. Germany Iarch 7, 1930.

The present invention relates to centrifua-l governors for the automatic control of ignition devices suitable for use with internal combustion engines.

1 In a known form of construction a spring tendin to retard the displacement of the centri gal weights is secured at one end at a point on a base plate which is connected to one half of the shaft and on the other l0 end at a point on an arm which is coupled with a cam which is connected to the other half of the shaft. This point is displaced at such la distance from the axis of the cam that it travels over a long path which is I3 suflicient for the tensioning of the spring. The characteristic line for the opposing force of the spring, as this is only tensioned in the straight direction, in addition to the spring constant, is dependant solely upon the path corresponding to the angle of adjustment of the cam about which 'path the spring is tensioned. The curves of the opposing force in dependence upon the angle of adjustment of the cam always have the same character.

The possibility of iniuencing the form of -tlie curve of the adjustment of the cam is very much limited thereby. More particularly, it is impossible to obtain a very speedy increase at the commencement of the adjustment and in connection therewith to obtain a slow steady rise during the further increase in rotation.

The object of the present invention is to eliminate this restriction and accordingly ythe springs opposing the displacement of the weights are tensioned substantially trans'- versely to their longitudinal axis by arms which are rigidly connected to one of the ,n two halves of the governor.

The invention is more particularly described with reference to the accompanying- Figure 1 is a longitudinal section of a flywheel governor.

Figure 2 is a plan view of the same in a position of fest.

Figure 3 is a plan view of the same in a working position.

Figure 4 is a plan view of a modified form of construction in the position of rest.

Figure 5 is a section of a spring adjusting device.

Figure 6 is an inverted plan view of Figure 5.

Adriving shaft 1 is provided with a flange 2 to which is coupled a base-plate 3 of the governor. The sleeve 5 for adjusting the cam is rotatably mounted with the cam 6 on an extension 4 of the drivingshaft.. Fingers 7 and arms 8 are formed on a disc which is rigidly connected to the cam. The fingers 7 engage in recesses 9 of centrifugal weights 10 which are pivotally mounted on bolts 11 secured to the base plate 3, and which slide on bearing pads 30, 31, on the base plate 3 in order to reduce friction. Return springs 12 are disposed between bolts 13, which are also secured to the base plate 3, and points 14 on the disc which lie adjacent the axis of angular displacement of the cam. The arms 8 are providedy with faces 150i predetermined curvature over which the springs 12 are tensoned in the working position.

The modified form of construction illustrated in Figure 4 differs from that already described solely in that the centrifugal Weights 10 are provided with arms 16 which act on two arms 17 connected to the cam 6,

in such a way that when the speed of rotation of the motor is increasing the effective displacement of the lever arm of the centrifugal weightbecomes greater whilst that of the cam becomes smaller. The result of this is that with similarly increased speeds of rotation the return spring in the second construction is not tensioned so much as that in the first construction.

The principle ,involved in the method of operation of the governor can be clearly seen from Figures2 and 3. It should however be remarked that the angular adjustment of the cam can beA thoroughly influenced by the lshape of the operating surfaces of the arms 16and 17 and by the shape of the faces 15 of middle` the spring tension increases quickly from this point as the spring deviates transversely, as shown in Fig. 3, to a greater extent than corresponds to the angle of adjustment of the cam because of the long lever arm with which the spring engages and because the components of the spring tension increase quickly. As a result, after the point at which the arm 8 strikes the spring, for the same increase in the Velocity'of the motor the cam will be angularly adjusted to a substantially lower amount than at the beginning of the adjustment. The tension which the spring receives at the beginning ot the adjustment through the change in angular position of the point of suspension 14 is quite unimportant as this point only travels for a short distance about the axis of the cam as a result of its short distance from said axes.

In order to enable the ready adjustment of the springs the bolts 19, Fig. 5, by which they are held are preferably secured to the stay 20 rotatably adjustable about the flange 2. This stay 20 is secured to the base plate 3 by two screws 21 and can be adjusted with regrd vto the base plate by an eccentric screw We claim:

l. A centrifugal governor comprising a driving member, a driven member, centrifugal weights pivotally mounted on said driving member, spring secured at one end to one member and at the other end to the other of .said -members and means to distort said springs normal to their longitudinal axes on rotation of said driving member and displacement of saidweights. y

2. A centrifugal governor comprising driving and driven coaxial members, centrifugal weights pivotally mounted on said driving memberv adjacent the periphery thereof, springs each secured at one end to said driving member and at the other 'end to said driven member, and means secured to said driven lnember for distorting said springs in a direction normal to their axes on the displacement 4of said means by said weights.

3. A centrifugal governor comprising driving and driven coaxial members, centrifugal weights pivotally mounted on said driving member adjacent the periphery thereof, springs each secured at one end to said driving member and at the other end to said. 

